Buggy code:
public class DefaultPartPresentation extends StackPresentation { private PaneFolder tabFolder ; private IPresentablePart current ; private int activeState = StackPresentation . AS_INACTIVE ; private MenuManager systemMenuManager = new MenuManager ( ) ; private Label titleLabel ; private Listener dragListener ; private int dragStart = - 1 ; private static final String TAB_DATA = ( DefaultPartPresentation . class . getName ( ) ) + ".partId" ; private PaneFolderButtonListener buttonListener = new PaneFolderButtonListener ( ) { public void stateButtonPressed ( int buttonId ) { } public void closeButtonPressed ( CTabItem item ) { } public void showList ( CTabFolderEvent event ) { } } ; private MouseListener mouseListener = new MouseAdapter ( ) { public void mouseDown ( MouseEvent e ) { } public void mouseDoubleClick ( MouseEvent e ) { } } ; private Listener menuListener = new Listener ( ) { public void handleEvent ( Event event ) { } } ; private Listener selectionListener = new Listener ( ) { public void handleEvent ( Event e ) { } } ; private IPropertyListener childPropertyChangeListener = new IPropertyListener ( ) { public void propertyChanged ( Object source , int property ) { } } ; private DisposeListener tabDisposeListener = new DisposeListener ( ) { public void widgetDisposed ( DisposeEvent e ) { } } ; private ToolBar viewToolBar ; private boolean shellActive = true ; private ShellListener shellListener = new ShellAdapter ( ) { public void shellActivated ( ShellEvent e ) { } public void shellDeactivated ( ShellEvent e ) { } } ; private IPropertyChangeListener themeListener = new IPropertyChangeListener ( ) { public void propertyChange ( PropertyChangeEvent event ) { } } ; public DefaultPartPresentation ( PaneFolder control , IStackPresentationSite stackSite ) { } public void restoreState ( IPresentationSerializer serializer , IMemento savedState ) { } public void saveState ( IPresentationSerializer context , IMemento memento ) { } public void init ( ) { } protected void setTitleAttributes ( ) { } protected final void setInactiveTabColors ( ) { } protected final void setActiveTabColors ( ) { } protected void updateGradient ( ) { } protected int computeTabHeight ( ) { } protected String getPaneName ( ) { } public void showPaneMenu ( ) { } protected IPresentablePart getCurrent ( ) { } private final int indexOf ( IPresentablePart part ) { } protected final CTabItem getTab ( IPresentablePart part ) { } protected void childPropertyChanged ( IPresentablePart part , int property ) { } protected final IPresentablePart getPartForTab ( CTabItem item ) { } protected PaneFolder getTabFolder ( ) { } public boolean isDisposed ( ) { } public void drawGradient ( Color fgColor , Color [ ] bgColors , int [ ] percentages , boolean vertical ) { } public boolean isActive ( ) { } public int getActive ( ) { } protected String getCurrentTitle ( ) { } protected void layout ( boolean changed ) { } protected void setControlSize ( ) { } protected IPartMenu getPartMenu ( ) { } public void dispose ( ) { } public void setActive ( int newState ) { } private CTabItem createPartTab ( IPresentablePart part , int tabIndex ) { } protected void initTab ( CTabItem tabItem , IPresentablePart part ) { tabItem . setText ( part . getName ( ) ) ; tabItem . setImage ( part . getTitleImage ( ) ) ; String toolTipText = part . getTitleToolTip ( ) ; if ( ! ( toolTipText . equals ( ZERO_LENGTH_STRING ) ) ) { tabItem . setToolTipText ( toolTipText ) ; } FontRegistry registry = PlatformUI . getWorkbench ( ) . getThemeManager ( ) . getCurrentTheme ( ) . getFontRegistry ( ) ; if ( part . isBusy ( ) ) tabItem . setFont ( registry . getItalic ( TAB_TEXT_FONT ) ) ; else { <START_BUG> tabItem . setFont ( registry . get ( TAB_TEXT_FONT ) ) ; <END_BUG> } } public void addPart ( IPresentablePart newPart , Object cookie ) { } public void addPart ( IPresentablePart newPart , int index ) { } public void removePart ( IPresentablePart oldPart ) { } public void selectPart ( IPresentablePart toSelect ) { } public IPresentablePart getCurrentPart ( ) { } public void setBounds ( Rectangle bounds ) { } public Point computeMinimumSize ( ) { } public void setVisible ( boolean isVisible ) { } public void setState ( int state ) { } public IMenuManager getSystemMenuManager ( ) { } protected void showSystemMenu ( Point point ) { } public Control getControl ( ) { } public StackDropResult dragOver ( Control currentControl , Point location ) { } protected Control getCurrentToolbar ( ) { } public void showSystemMenu ( ) { } public Control [ ] getTabList ( IPresentablePart part ) { } protected void showList ( Shell parentShell , int x , int y ) { } public void showPartList ( ) { } void setSelection ( CTabItem tabItem ) { } void close ( IPresentablePart [ ] presentablePart ) { } List getPresentableParts ( ) { } Image getLabelImage ( IPresentablePart presentablePart ) { } String getLabelText ( IPresentablePart presentablePart , boolean includePath ) { } protected boolean isShellActive ( ) { } }

Fix:
tabItem . setFont ( null ) ;